Wow.......iPhone 6splus

Wow.......iPhone 6splus

I purchased a iPhone 6s + from boost Mobile website......paid next day shipping ......got it in 4 days.....AND THEN boost shipped me a iPhone that was already activated on Sprint mobile with someone else's account....I have been waiting since Nov 8 for them to deactivate it so I can use it....I have called many times sometimes they say no record of it and sometimes they say it's in the works. My daughter (17) used here first paycheck she has ever made on it with am I to do.....nobody at boost will help.....just like with my max xl in recent post.....so what do I do.......what the heck am I supposed to do.....support is so crappy .......